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I've got the same problem... Smokes like crazy, but is running about 100 hp shy of what I'm almost positive it should be putting down.. I'm just about ready to send the pump somewhere and have it tuned properly and just hope it works...

I've got the same problem... Smokes like crazy, but is running about 100 hp shy of what I'm almost positive it should be putting down.. I'm just about ready to send the pump somewhere and have it tuned properly and just hope it works...

Silly question- did you dyno with those wheels and tires? We've seen weird things happen at the drag strip when we swap stock wheels for 18's or 20's. Some have lost as much as 4 tenths with the bigger tires..

Silly question- did you dyno with those wheels and tires? We've seen weird things happen at the drag strip when we swap stock wheels for 18's or 20's. Some have lost as much as 4 tenths with the bigger tires..

I had 305/70/16's on at the time, they're actually shorter then a 285/75/16. I also had a blown head gasket, it ran 414 on a mustang dyno. But I don't think the head gasket had anything to do with it. Wasn't opened up between the cylinders, just the water and oil journals..

Looks to me like smkn should be higher then me given them mods and I was hoping to break 500

Well for a comparison, I dyno'd 477hp with my plate and afc slid all the way back, and the turbos did not light until just shy of 2000rpm.
This may or may not help. Was the dyno putting enough load on the motor? That was my problem, trying to get the turbos to light.
Tim.

Am i doing something wrong when I dyno? I ran it up to 55, locked the converter, then punched it out to 120.

i think u have too much fuel

and its puttin out the fire..

setup with ur turbo should really light up and have plenty of power.. I feel that u have plenty of fuel, perhaps too much actually. check the fuel pressure with a gauge.... the gutted AFC dont help none either and teh rack travel mod well, i did feel a difference on my 215 pump... so i can argue with teddy bear there... no offense man...

anyways

did u start ur dyno run at 1500 or so RPMS? if so did the truck feel boggy? how much boost did you see? what were ur pyro readings? all of this comes into play..

im at a similar problem with my truck with 370s and 181s... with the twins i made only 450 horses, But u will learn that too much fuel will put out the fire too quickly and then clean up too easily once the chargers light, IE what happened with me with 16.5 degrees of timing on one of my last dyno runs, the chargers were lighting when i was out of RPMS due to too much fuel early on..

Just a consideration.. just get some tuning done or mess with it a bit longer and ull get it better...

Rick

__________________ 05 3500 auto 4x4

95 2500 5 spd 4x4

HUGE thanks to Dan and the boys at Valair Inc Clutch and Gomer at onesourcetruckaccessories!

Can the rack plug detrimentally affect performance if the plate is slid back far enough to prevent rack travel past 16-17mm?
Why not leave it in and keep the plate slid back a bit rather than take the pump off again to put the stock one back in?

Can the rack plug detrimentally affect performance if the plate is slid back far enough to prevent rack travel past 16-17mm?
Why not leave it in and keep the plate slid back a bit rather than take the pump off again to put the stock one back in?

That's what I was thinking....but?
When my pump was on the bench I asked them to set the pump @ 17mm of max travel and they needed to slide my 0 plate full back to attain this, however I don't know if you could easily measure this with the pump on?

What's this "rack mod" being referred to? Is this the rack plug change? If so, it won't make any difference. The plug doesn't affect rack travel. The stop plate does. Max rack travel is 21 mm on all pumps due the rack stop pin. Once max rack travel is reached, delivery valves are about the only thing that will affect fuel delivery on an otherwise stock pump. As 21 mm of rack travel is approached on the 215 pumps you get into the start-up notch on the plunger head. That will provide more fuel, but usually results in higher EGTs with minimal power improvements.

What's this "rack mod" being referred to? Is this the rack plug change? If so, it won't make any difference. The plug doesn't affect rack travel. The stop plate does. Max rack travel is 21 mm on all pumps due the rack stop pin. Once max rack travel is reached, delivery valves are about the only thing that will affect fuel delivery on an otherwise stock pump. As 21 mm of rack travel is approached on the 215 pumps you get into the start-up notch on the plunger head. That will provide more fuel, but usually results in higher EGTs with minimal power improvements.

-Jay

Hi Jay,

If there is no stop/curve plate in the pump, the other plugs can allow the rack to travel past 21mm's. This does no good in making power anyway, just smoke and heat.

Personally I dont like modded DV's or the DV's currently used from other pumps like the 191's, etc.

DV's can add fuel by removing less volume from the line, but they cause many other problems. Good old 181's for me please

If there is no stop/curve plate in the pump, the other plugs can allow the rack to travel past 21mm's. This does no good in making power anyway, just smoke and heat.

Hey, Don.

Now before I go on, let me qualify my comment. I am certainly no pump guru. I haven't taken any apart. My info comes from some long conversations with 2 Bosch certified techs with more than 40 years experience between them that both said the stop pin limits rack travel to 21 mm - no ifs, ands, or buts. This conversation occurred while they were rebuilding mine after a governor calamity. They had the dial gauge in the end and showed me full rack travel possible, from 0 to 21 mm. No plate in the pump at the time. They said that's all there is and there ain't no more.

So I have to ask, where's my disconnect here? Is there a part of the story that I'm missing? I'd really like to get this resolved so I don't make a fool of myself.